Shut down without showing a confirmation dialog:
osascript -e 'tell app "System Events" to shut down'
Shut down after showing a confirmation dialog:
osascript -e 'tell app "loginwindow" to «event aevtrsdn»'
Restart without showing a confirmation dialog:
osascript -e 'tell app "System Events" to restart'
Restart after showing a confirmation dialog:
osascript -e 'tell app "loginwindow" to «event aevtrrst»'
Log out without showing a confirmation dialog:
osascript -e 'tell app "System Events" to «event aevtrlgo»'
Log out after showing a confirmation dialog:
osascript -e 'tell app "System Events" to log out'
Go to sleep (pmset):
pmset sleepnow
Go to sleep (AppleScript):
osascript -e 'tell app "System Events" to sleep'
Put displays to sleep (10.9 and later):
pmset displaysleepnow